Experimental evaluation of an eco-friendly grinding process combining minimum quantity lubrication and graphene-enhanced plant-oil-based cutting fluid

Abstract Minimum Quantity Lubrication (MQL) is increasingly applied in the grinding process of the hard-to-cut material (HCM) as an eco-friendly and efficient technology of lubricating and cooling. The grinding characteristics of the HCM directly affect their reliability and serviceability and so, evaluating the grinding characteristics during the MQL is very vital. In this work, the MQL with different weight concentrations of graphene-enhanced plant-oil-based cutting fluids (POBCFs) (0.05 wt%, 0.1 wt%, 0.15 wt%, and 0.2 wt%) was adopted in the grinding of the TC4 alloy, where the graphene nanoparticle (GPNP) was added to the POBCF for preparing the graphene-enhanced POBCF for improving the grinding characteristics of the TC4 alloy. The experimental evaluation of the grinding characteristics of the TC4 alloy was carried out through the grinding experiments during the six working conditions (dry, pure MQL (PMQL), and four graphene MQL (GMQL)), and the optimal working condition was the GMQL (0.1 wt%). The influence mechanisms of the GPNP on the grinding characteristics with respect to the grinding force, grinding temperature, specific grinding energy, and surface integrity were revealed. In summary, the oil films generated during the grinding area exhibit excellent cooling and lubricating performances and the appropriate amount of GPNPs can strengthen the oil film performances in both cooling and lubricating to improve the grinding characteristics. The research results show that the GPNP exhibits a remarkable impact in improving the grinding characteristics and provide the experiment basis for applying the GPNP to the MQL grinding.